/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.log4j.helpers;

import java.util.Calendar;
import java.util.TimeZone;
import java.util.Date;
import java.text.FieldPosition;
import java.text.ParsePosition;
import java.text.DateFormatSymbols;

/**
 * Formats a {@link Date} in the format "dd MMM yyyy HH:mm:ss,SSS" for example,
 * "06 Nov 1994 15:49:37,459".
 * 
 * @author Ceki G&uuml;lc&uuml;
 * @since 0.7.5
 */
public class DateTimeDateFormat extends AbsoluteTimeDateFormat {
	private static final long serialVersionUID = 5547637772208514971L;

	String[] shortMonths;

	public DateTimeDateFormat() {
		super();
		shortMonths = new DateFormatSymbols().getShortMonths();
	}

	public DateTimeDateFormat(TimeZone timeZone) {
		this();
		setCalendar(Calendar.getInstance(timeZone));
	}

	/**
	 * Appends to <code>sbuf</code> the date in the format "dd MMM yyyy
	 * HH:mm:ss,SSS" for example, "06 Nov 1994 08:49:37,459".
	 * 
	 * @param sbuf
	 *            the string buffer to write to
	 */
	public StringBuffer format(Date date, StringBuffer sbuf,
			FieldPosition fieldPosition) {

		calendar.setTime(date);

		int day = calendar.get(Calendar.DAY_OF_MONTH);
		if (day < 10)
			sbuf.append('0');
		sbuf.append(day);
		sbuf.append(' ');
		sbuf.append(shortMonths[calendar.get(Calendar.MONTH)]);
		sbuf.append(' ');

		int year = calendar.get(Calendar.YEAR);
		sbuf.append(year);
		sbuf.append(' ');

		return super.format(date, sbuf, fieldPosition);
	}

	/**
	 * This method does not do anything but return <code>null</code>.
	 */
	public Date parse(java.lang.String s, ParsePosition pos) {
		return null;
	}
}
